Before there were airplanes, there were airships.
Dirigibles, sometimes known as Zeppelins, blimps, or airships, are “lighter than air” aircraft filled with gas that is less dense than the nitrogen-oxygen atmosphere. In the past hydrogen gas was used; these days, helium is preferred.
The first truly successful experimental rigid airship was the Zeppelin LZ1. On this date in 1900, it was flown from a floating hangar on Lake Constance, in Southern Germany. That first flight carried five people more than three miles in 18 minutes. Wind forced an emergency landing on the water.
Even though this first Zeppelin weighed 13 tons, the 17 gas cells, each covered in rubberized cloth, was able to hold enough hydrogen gas to lift the airship. It was steered by two rudders, and it was propelled by four propellers. Passengers and crew were carried in two six-meter-long aluminum gondolas suspended underneath.
Count von Zeppelin couldn't interest enough investors and had to dismantle this early airship and sell the parts for scrap. Later, the Zeppelin LZ2 was much more successful, and rigid airships were built, flown, tested, and used by public, military, and businesses. Various European countries used rigid airships during World War I for scouting and bombing missions.
Between the World Wars, some airships were used to carry passengers between continents—from Germany to Brazil and from Germany to the United States. Airships could carry many more passengers than could the airplanes of the time. The ride on an airship was also much more comfortable—comparable to traveling by ocean liner. There was far less engine noise, vibration, and turbulence than in the 1930s airplanes, and Zeppelins featured private cabins, observation decks, dining rooms, and even a smoking lounge. Zeppelins were faster than ocean liners—the Brazil-Germany transit took just 68 hours (less than three days) via Zeppelin; the same trip would take between a week and month via ocean liner.
However, there were enough deadly accidents to make some countries and businesses and people abandon the idea of shipping and traveling by airship. And in 1937, the spectacular and much-publicized Hindenburg disaster, which killed 13 passengers, 22 aircrew, and one American ground-crewman, effectively ended the Golden Age of the Airship.
Hydrogen is highly flammable; helium, however, is considered a “noble” gas because it does not readily combine with other elements and therefore doesn't burn. It seems that the Zeppelin corporation in Germany was interested in flying rigid airships with helium but lacked the ability to produce helium. The United States had the technical ability to produce helium but refused to sell it to Germany. Nowadays helium-filled airships are sometimes used for advertising, sightseeing, surveillance, and research.